PsychoLogical
Black and White, Yin and Yang, Light and Dark.
I honestly don't care about him owning an Alolan Sandslash, just give Ash another fking Ice Type for keeps and not have him catch ONLY 1 after all these years after releasing the first and forgettable one. He now has more fking Rock, Dragon, and Dark types than Ice Types when he originally had NONE OF THEM when he had Glalie.Just give him Sandslash like he should have done in SM and he can catch whatever, I've waited a long long time for him to own a Sandslash and another Ice type...
And Obstagoon cause it's my favorite Galar Pokemon, and it'd be nice to have something else to throw at the "Ash can't catch evil/mean Pokemon!" crowd. That excuse is just annoying...